Gas-controlling mechanism.



G. A. ROBERTSHAW.

GAS CONTROLLING MECHANISM.

APPIQIOA'JZION FILED NOV. 9, 1912.

l 9 1 0?,549, Patented Aug. 18, 1914.

2 SHEETSSHEET 1. I

F g.1. v I l WITNESSES INUENTOR WWW Q QRARM e. A. ROBERTSHAW. GAS QONTROLLING MECHANISM. APPLIGATION FILED NOV. 9, 1912.

Patented Aug; 18, 1914;.

WRTNESSES INVENTOR TED s'rATEs GEORGE SLEY ROBERTSHAW, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO FREDERICK W. PROBERTSHAW, OF PITTSBURGH, PENNSYLVANIA.

GAS-CONTROLLING MECHANISM,

Specification of Letters Patent.

Patented Aug. 18, 19M...

Application filed November 9, 1912. Serial No. 730,401.

To all whom it may concern:

Be it known that I, GEORGE ANSLE-Y Roennrsrmw, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Gas-Controlling Mechanism, of which the following is a full,'clear, and exact descrip-.

tion, reference being had to the accompanying drawings, in which I Figure 1 is a side elevation partially in section of one form of apparatus for carrying out my invention; Fig. 2 is a vertical section on the line III1 of Fig. 3, of one form of gas cont-rolling apparatus; Fig. 3 is a similar view 011 the line IIIIII of Fig. 2; and Fig. 4 is a sectional View through another form of apparatus for controlling the gas to the several burners.

My invention is adaptable to water heaters, and more particularly to gas fired heaters having a heating element in which the water is heated, and which is connected with a storage drum or reservoir.

My invention relates more particularly to thermostatically controlled Valve mechanism for controlling the gas supply to the main and pilot burners.

One of my objects is, to provide mechanism of this character which will operate to automatically cut off the supply of gas to the pilot burner when the main burner is in operation, and to automatically restore such supply prior to cutting oil the supply to the main burner when the water has been heated to a predetermined temperature. In this manner the pilot burner is in operation only when the main burner is shut ofi' or just prior thereto.

A further object is to provide a valve arrangement which will prevent overheating due to gas leakage. Heretofore in systems of this general character, any leakage of gas through the auxiliary thermostatically controlled valve acted to increase the gas supply to the main burner. In my system any such leakage immediately acts to close the main-valve and hold it closed.

My invention also provides a main valve which is moved from full open to full closed position practically instantaneously, thereby preventing such a reduction 1n the gas supply to the main burner as would cause flare backs.

It has been customary heretofore to provide the main valve with a by-pass to permit gas to pass to the opposite side of the valve and which gas was consumed by the pilot light, and as soon as the temperaturept the water was raised above a predetermined point, the thermostatic valves were closed and thereby prevented the gas from passing through the by-pass to the pilot light, and the accumulated pressure on the opposite side of the valve would close the main valve. In my arrangement, the thermostatic valve is opened when the temperature of the water rises above a predetermined point, and permits gas to flow to the pilot light, which is ignited from the flame from the main burner. This opening of the thermostatic valvepermits gas to enter a chamber on the opposite side of the main gas valve and close the passage through the main gas valve to the main burner; and as soon as the water cools down to a-predetermined temperature the thermostatic valve is closed which will relieve the pressure above the main valve and at the same time out ofl' the supply to the pilot valve. This relieving of the pressure on the opposite side of the main valve will permit the gas to flow to the main In Figured of the drawings, 1 have shift- Y ed the supply pipes to the pilot light and the main burner, so that these pipes will lie in the same vertical plane as the inlet pipe to the valve, although it will be understood that the pipes may be connected to any convenient point to meet various requirements.

Referring to Figs. 1 to 3, the numeral 2 designates the heater, having a heating coil 3, which is connected to the bottom of a boiler or container 4 by means of a pipe 5. The top of the coil is connected to the top of the boiler in any desired manner so that there is a circulation of water through the heating coil and the boiler when the burner is in operation.

6 designates the main burner which is located below the heating coil 3, and 7 is a gas supply pipe therefor extending from a valve casing 8.

9 is a pilot burner adjacent to the main burner 6 and connected by means of a supply pipe 10 with a valve casing 8. Leading to the casing 8 from any suitable gas sup ply is a pipe 11, provided with a controlling valve 12 for controlling the supply of gas to the casing 8. The casing 8 is' connected to a coupling 13 which is connected to the pipe 5 and to the bottom of the boiler; and extending upwardly from the casing 8 through the coupling 13 is a thermostat 14.

The casing 8 is divided into three separate chambers which I have indicated at 15, 16

and 17 The chambers 15 and 16 are separated from each other by means of a diaphragm valve 18; the pipes 7 and 11 being in communication with the chamber 15 while the pipe 10 is in communication with the chamber 16. The chamber 17 is in communication with the chamber 15 by means of a by-pass 19 so that pressure from the main supply pipe 11 is constantly admitted to the chamber 17. Mounted within the chamber 17 is a valve 20 which is arranged to open, and close communication between the chambers 16 and 17 through the port 21. Extending upwardly from the valve 20 and through a portion of the casing 8 is a valve stem 20*; and surrounding the valve stem 20 is a coil spring 22 which engages a boss on the upper end of the stem and the casing, and is arranged to move the valve 20 from its seat to open communication between the chambers 16 and 17. Connected to the upper end of the stem 2O by means of a screw threaded engagement therewith is an arm 23 which extends outwardly through an opening in the casing 8 and is arranged to permit the adjustment of the stem 20* to cause the valve 20 to be opened when the desired temperature of the water has been reached. The lower end of one of the members of the thermostat 1 1 rests on the upper portion of I and thence to the burner 6" through the pipe the arm 23, as indicated in Fig. 2, and is arranged to hold thev valve downwardly onits seat when the temperature of the water is below a predetermined point and thereby close communication between the chambers 17 and 18.

The operation of this device is as follows :-Assuming the parts to be in the position shown in Figs. 2 and 3 at whichtime the water within the boiler is cold, the valve 12 is opened to admit gas to the chamber 15 7 As soon as the temperature of the water has been raised above a predetermined point, I

the thermostat 14 will permit the spring 22 to raise the valve 20 from its seat, which will permit the gas to flow from -the port 19 through the port 21 to the chamber 16 above the diaphragm valve 18. A pressure is thus built up along the diaphragm suflicient to move the valve 18 to its seat 2%, and shut off the gas supply to the pipe 7. As soon as gas is admitted to the chamber 16, gas will be supplied to the pilot burner 9 through the pipe 10, which will be ignited before the gas is cut off from the main burner 6. As soon as the water is again cooled down below a predetermined temperature, the thermostat will act to close the valve 20 and out 01f communication from the gas supply tothe chamber 16. The pressure within said chamber will immediately be relieved by the gas flow from said chamber to the pilot burner and i will permit the valve 18 to be raised from its seat 24 and permit gas to flow tothe main burner 6 through the pipe 7, which will be ignited before the pilot light is extinguished.

The area of this valve controlled opening is large enough to permit suflicient gas to pass between the valve and its seat to supply the main burner even though the valve has only been raised slightly from its seat.

In Fig. 4 I have shown a modified a'rrangement in which the main valve and the thermostatic valve are within separate casings. In this arrangement themain valve 18* is within a casing 8 and separates the easing into two chambers 15 and 16 The gas supply pipe 11 leads into the casing 8 in a manner similar to that shown in Figs. 2 and 3. The valve 18 in this construction is also arranged to be moved on to its seat 24 when gas is admitted to the chamber 16 in a manner similar to the construction shown in Figs. 2 and 3. In this arrangement gas is admitted to the chamber 16 from the pipe 11 through a pipe 19 the flow of gas'being controlled by a thermostatically cont-rolled valve 20". The pilot burner 9*- is connected to the pipe 19* between the thermostatic valve 20? and the main valve casing. The operation of this device is precisely the same as the operation of the device shown in Figs.

2 and 3.

If it is desired to maintain an auxiliary pilot light burning at all times, said pilot light can be connected to the point indicated at 25 in Figs. 2 and 3, or can be connected to any portion of the supply pipe in the construction shown in Fig. 4.

The advantages of my invention result from the provision of gas controlling mechanism which is arranged'to quickly open and close the supply to the main burner to avoid flarebacks; second from the provislon of means for cutting ofi the supply of gas to the pilot li ht when the main burner is burning; third, from the provision of a thermostatically dontrolled valve which is arranged to simultaneously control the flow of gas to the pilot light and to control the closing of the main supply valve when the water has been heated to a predetermined temperature. Alsofrom the provision of a thermostatically controlled valve which is arranged to be opened when the temperature of the water rises above a predetermined point and to be closed when the temperature of the Water falls below a predetermined point. By the provision of a thermostatically controlled valve which is arranged to be opened when the temperature of the water has been raised above a predetermined point and thereby effect the closing of the main valve, I prevent overheating of the heating coils and burner due to leakage through the thermostatically controlled valve, as any leakage through the thermostatically cont-rolled valve will cause the main valve to be closed and thereby cut off the supply of gas to the mainburner. Further from the provision of a gas supply under pressure, I am enabled to use a Bunsen burner for a pilot burner or light.

I have described this device in connection with a water heater, although it will readily be understood by those familiar with the art, that the device can be used for controlling the flow of gas to a burner for heating purposes ozt any character.

I claim: 1. In the combination, a main burner, a

' pilot burner, a main gas valve opening under the pressure of gas from a supply main on one side and closing by a built-up pressure of gas at its other side, a conduit leading to said other side of the main valve and independent of said-valve, a supplemental -,valve which controls the said conduit and the building up of the closing gas pressure on said other side of the main valve,'a thermostat which controls the supplemental valve to admit or cut oil the gas supply to said other side of the main valve, and a sup- '-ply connection for the pilot burner having a portion which leads outwardly to the pilot burner from said other side of the main valve, substantially as described.

2. In the combination, a main burner, a

a pilot burner, a main gas valve opening unply connection leading from said conduit at der the pressure of gas from a supply main on one. side andclosing by a built-up pressure-of gas at its otherfside, a conduit leading to said other side of the main valve and independent of said valve, a supplemental valvej WhlCh'COlliiI'OlS the said conduit and the building up of the closing gas. pressure on saidother side of the main valve, a thermostat which control the supplemental valve to admit or opt oil the gas su ply to said other side of the main valve, an a supply connection for the pilotlighhsaid supa point between the sup lemental valve and the said other" side of t e main valve, sub stantially as described.

' 3. In combinations mam gas burner and apilot burner arranged to light eachother, valve mechanism controlling the gas supply to the said burners including a main valve.

opening under the full pressure of gas from the main on one side thereof and closing by pressure of gas on the other s1de, and iiieluding also a supplemental valve control ling the said closing gas pressure, said supplemental valve controlling also the supply of gas to the pilot burner and cutting ofl said supply to extinguish the pilot light after the main burner has been lighted, and supplying gas to the pilot light just before the main burner is extinguished, and a ther-. mostat controlling the said supplemental valve; substantially as described.

a In combination amain and a pilot burner a main gas valve, opening under the pressure of gas from the main on one side and closing by pressure of gas on its other side, a supplemental valve controlling the building up'of the closing gas pressureon said other side of the main valve, and a thermostat controlling the supplemental valve to admit said closing ga pressure or to cutit off, and a connection to supply the pilot light also control-led by said supplemental valve; substantially as described.

5. A heating other, a gas supply passage for the main burner, a diaphragm chamber through. which said gas supply passage leads, a diaphragm system comprising a main "burner and a pilot burner, each of said-burn: ers being arranged to be lighted by the' in said chamber, a valve carried'by the diaphragm, for controlling said passage, a gas;

supply passage for the pilot burner, said passage also leading to' the opposite side of the diaphragm, and a thermostatic valve lop I cated in the last "named passage and controlling both the gas supply to the pilot i burner and to the opposite side of the diaphragm; substantially as described.

6; A heating system comprising a main burner and a pilot burner, each of saidburhers being arranged to be .lighted by the 1" other, a gas supplypassage tor the .main

in burner, a diaphragm chamber through which said supply passage extends, a diaphragm in said. chamber, a valve carried by said diaphragm -for controlling said pas sage, a gas supply' passage for the pilot burner, said passage also leading to the opposite side of the dia hragm, and a thermostatic valve locatedm the last'named passage and controlling bothithe gas supply to the pilot burner and to the opposite slde of.

the diaphragm, said diaphragm valve being wholly controlled by the action of the thermostatic valve; substantially as described.

7. In a heatin system, a. main burner, a pilot burner, eac of said burners being ar ranged to be lighted'by the other,' a. diaphragm valve for controlling the gas supply for the main burner, a source. of supplythe pilot burner independent of the dia 4 hragm valve, and. a thermostatic valve forcontrolling the gas supply to the pilot burner, said thermostatic valve also acting to control the closing pressure on the diaphragmvalve and thereby the gas supply to the main valve; substantially as described.

8. A heating system comprising a main burner, a gas supply passage therefor, a single main valve for automaticallycontrolling the gas supply to the main burner, a pilot burner, a source of supply for the pilot burner independent of the diaphragm valve, a thermostatic valve for controlling the gas supply to the pilot burner, and gas-pressure operated means controlled by the thermostatic valve whereby the opening of the thermostatic valve effects the closing of the main valve and whereby the closing of the thermostatic valve effects the opening of the main valve; substantially as described.

9. A heating system comprising a main burner, a gas supply passage therefor, a diaphragm chamber through one side of which the said gas supply passage leads, a diaphragm in said chamber, a valve controlled by the diaphragm and arranged to control said passage, a pilot burner, a gas supply for the pilot burner which is independent of the main valve, a connection leading from the pilot burner to the opposite side of the diaphragm chamber, and a thermostatic valve arranged to control the supply of gas to the pilot burner and also to the opposite side of the diaphragm chamber; substantially as described.

10. In combination a main and a pilot burner, a main gas valve opening under the pressure of gas from the main on one side and closing by a pressure of gas on its other side, a supplemental valve for controlling the building-up of the closing gas pressure on said other side of the main. valve, and a thermostat controlling the supplemental valve to admit said closing gas pressure or to cut it ofi', said pilot burner taking care of the gas escaping from the closing pressure side of the main Valve, said pilotlight supply being independent of the main valve, and the supplemental valve being arranged to control such independent connection; substantially as described.

11. In combination a main gas burner and a pilot burner arranged to light each other, valve mechanism controlling the gas supply to the said burners, and a thermostat for controlling the valve mechanism to cut off the gas supply to the pilot as soon as the main burnerhas been lighted by the pilot,

and to cut off the gas supply to the main burner after the pilot has been lighted by the main burner, the valve mechanism for controlling the supply'to the main gas burner having means whereby itis con trolled by changes in gas pressure effected by the opening and closing of the valve mechanism controlling the supply to the pilot burner; substant1ally as described.

12. In combination a main gas burner and a pilot burner, arranged to light each other, valve mechanism controlling the gas supply to the said burners, and a thermostat controlling the valve 'mechanism to supply gas to the main burner and put out the pilot burner after the main burner is lighted by the pilot, and to supply gas to the pilot burner and put out the main burner after the latter has lighted the pilot burner, the valve mechanism for controlling the supply to the main gas burner having means Whereby it is controlled by changes in gaspressure effected by the opening and closing of the valve mechanism controlling the supply to the pilot burner; substantially as described.

In testimony whereof, I have hereunto set my hand.

GEORGE AJNSLEY ROBERTSHAW. 

